UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number 001-39103 CABALETTA BIO, INC. (Exact name of Registrant as specified in its Charter) Delaware 82-1685768 (State or other jurisdiction of ...

2 Cabaletta Bio° CARTA Strategy | CABA-201 (4-1BB CD19-CAR T) expecting 1H23 IND clearance1 CAART Strategy | DSG3-CAART & MuSK-CAART clinical studies evaluating combination regimens CAART – Chimeric AutoAntibody Receptor T cells; CARTA – Chimeric Antigen Receptor T cells for Autoimmunity; IND – Investigational New Drug; SLE – Systemic lupus erythematosus; RA – Rheumatoid arthritis 5 Chimeric Antigen Receptor T cells for Autoimmunity Fully Human Anti-CD19 Targeting Domain In autoimmune diseases with a limite ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from_______________ to _______________ | --- | --- | |-----------------------------------------------------------------------------------------|----------------- ...

Cabaletta Bio° Corporate Presentation SEPTEMBER 2022 © 2022 Cabaletta Bio. All rights reserved. Disclaimer The following presentation, including any printed or electronic copy of these slides, the talks given by the presenters, the information communicated during any delivery of the presentation and any question and answer session and any document or material distributed at or in connection with the presentation (collectively, the "Presentation") has been prepared by Cabaletta Bio, Inc. ("we," "us," "our," ...

Cabaletta Bio° Corporate Presentation AUGUST 2022 © 2022 Cabaletta Bio. All rights reserved. Disclaimer 2 The following presentation, including any printed or electronic copy of these slides, the talks given by the presenters, the information communicated during any delivery of the presentation and any question and answer session and any document or material distributed at or in connection with the presentation (collectively, the "Presentation") has been prepared by Cabaletta Bio, Inc. ("we," "us," "our," " ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 Non-accelerated filer ☒ Smaller reporting company ☒ FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from_______________ to _______________ Commission File Number: 001-39103 CABALETTA BIO, INC. (Exact Name of Regist ...

Cabaletta Bio° Corporate Presentation MAY 2022 © 2022 Cabaletta Bio. All rights reserved. Disclaimer 2 The following presentation, including any printed or electronic copy of these slides, the talks given by the presenters, the information communicated during any delivery of the presentation and any question and answer session and any document or material distributed at or in connection with the presentation (collectively, the "Presentation") has been prepared by Cabaletta Bio, Inc. ("we," "us," "our," "Cab ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from_______________ to _______________ Commission File Number: 001-39103 CABALETTA BIO, INC. (Exact Name of Registrant as Specified in its Charter) Delaware (State o ...

Cabaletta Bio° Corporate Presentation MARCH 2022 © 2022 Cabaletta Bio. All rights reserved. Disclaimer 2 The following presentation, including any printed or electronic copy of these slides, the talks given by the presenters, the information communicated during any delivery of the presentation and any question and answer session and any document or material distributed at or in connection with the presentation (collectively, the "Presentation") has been prepared by Cabaletta Bio, Inc. ("we," "us," "our," "C ...

Cabaletta Bio° Corporate Presentation MARCH 2022 © 2022 Cabaletta Bio. All rights reserved. Disclaimer 2 The following presentation, including any printed or electronic copy of these slides, the talks given by the presenters, the information communicated during any delivery of the presentation and any question and answer session and any document or material distributed at or in connection with the presentation (collectively, the "Presentation") has been prepared by Cabaletta Bio, Inc. ("we," "us," "our," "C ...